Integrating SEM-PLS and NCA to reveal the mediating role of leaf nutrient status in linking soil nutrient availability and oil palm yield in peatlands

Ireng Darwati; Muchamad Yusron; Joko Purnomo; Rudi Suryadi; Devi Rusmin; Octivia Trisilawati; Edi Yatno; Joko Pitono; Nurjaya; Djajadi; Muhammad Syakir; Eni Fidiyawati; Rr Sri  Hartati

doi:10.17268/sci.agropecu.2026.012

Authors

Ireng Darwati Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-4861-9051
Muchamad Yusron National Research and Innovation Agency
Joko Purnomo Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0009-0001-0523-7328
Rudi Suryadi Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-4990-3150
Devi Rusmin Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-8661-1026
Octivia Trisilawati Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-2753-5289
Edi Yatno Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-4501-4305
Joko Pitono Research Center for Horticulture, National Research and Innovation Agency, Indonesia http://orcid.org/0000-0003-4967-077X
Nurjaya Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0009-0000-6824-1992
Djajadi Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0003-0931-4519
Muhammad Syakir Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0002-8185-8783
Eni Fidiyawati Research Center for Estate Crops, National Research and Innovation Agency, Indonesia https://orcid.org/0000-0001-6939-5264
Rr Sri Hartati Research Center for Estate Crops, National Research and Innovation Agency, Indonesia. https://orcid.org/0000-0003-4127-5564

DOI:

https://doi.org/10.17268/sci.agropecu.2026.012

Keywords:

Groundwater management, nutrient-soil management, peat soil, palm growth, soil chemistry

Abstract

The expansion of oil palm plantations into peatlands presents a critical area of study, particularly in understanding how nutrient dynamics and groundwater management influence oil palm yield. This research was conducted on smallholder oil palm plantations comprising 8–10-year-old palms cultivated on peat soils in Bengkalis Regency, Riau Province. A completely randomized block design was used, incorporating three groundwater table treatments: A. 40 cm, B. 60 cm, and C. 80 cm. Fertilizer application rates were as follows: urea at 2.50 kg/tree/year, SP-36 at 2.75 kg/tree/year, MOP (KCl) at 2.25 kg/tree/year, and dolomite at 2.00 kg/tree/year. Data analysis utilized a combination of Structural Equation Modeling based on Partial Least Squares (SEM-PLS) and Necessary Condition Analysis (NCA). The results showed that nutrient dynamics, indicated by leaf nutrient content, are the key driver connecting soil nutrient availability with oil palm yield. This finding emphasizes the importance of monitoring and managing nutrient flows through the plant to optimize fertilization strategies and improve yield performance. The combined use of SEM-PLS and NCA provides a robust analytical framework for understanding yield formation and developing nutrient management strategies for oil palm cultivation on peatlands.

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